Editorial
Proton beam therapy – Do we need the randomised trials and can we do them?

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Why proton (and light ion) beams?

The interest in proton beams, rather than the conventional photons and electrons, lies in the fact that protons can give much better dose distributions than the conventional beams. This means for virtually all clinical situations that the dose to the tumour target can be increased, meaning higher tumour control probabilities and/or the dose to normal, non-tumour containing volumes can be decreased, reducing the risks of normal tissue complications. The questions are, how much better, and are

The scientific evidence

The two reports [7], [8], although they both review the available scientific literature in a similarly systematic way, are very different in character. The first one is a Cochrane-like review performed in a very strict, bone-dry way leaving no room for much presentation of results or discussions about evidence from trials of other types than the randomised controlled clinical trials [7]. Since very few randomised trials were found, virtually no data are presented. You are as a reader basically

Why is the evidence so low?

A great number of reasons, or some would rather read ‘excuses’, can be put forward behind the virtual lack of evidence from prospective, particularly randomised trials. Until very recently, practically all proton (and light ion) treatments have been given at facilities built for physics research purposes, often severely reducing beam time availability. Most cancers are best treated with multiple fractions during many weeks, an impossibility at most sites. A dedicated centre for proton therapy

Do we need randomised trials?

Modern health care requires solid empirical evidence from conclusive trials and does not consider rationale arguments sufficient. Evidence-based medicine is the speciality seeking the evidence base from the trials, like in the two reports about proton (particle) beam therapy [7], [8], but has also been synonymous with that superiority, in at least one aspect, has to be proven in randomised trials (and meta-analyses or systematic overviews of these). Modern health care more and more also

Is it only a matter of cost-effectiveness?

All technical development in radiation therapy has meant more expensive treatments, but the theoretical arguments of superiority have been sufficient since the increased costs have been reasonable and possible to cover within the budget of a larger hospital. The equipment and building of proton beam facilities are always more expensive than those of conventional rays [22], and very few hospitals can cover these extra costs alone. This increases the demand for better scientific evidence than was

Can we run the (necessary) randomised trials?

This difficult question was discussed particularly by Olsen et al. [8] and has also been at least touched upon in a few other articles [7], [10], [16], [17], [19]. The opinions have ranged from that they are unethical, and thus impossible to run to that they must be done, however, without discussing how realistic this is. To embark upon and include patients in a randomised trial require that you are uncertain about the effects. The most conclusive trial is an upfront comparison of radiation

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